// Copyright 2020 The Dawn & Tint Authors
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its
//    contributors may be used to endorse or promote products derived from
//    this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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#ifndef SRC_DAWN_COMMON_TYPETRAITS_H_
#define SRC_DAWN_COMMON_TYPETRAITS_H_

#include <type_traits>

namespace dawn {

template <typename LHS, typename RHS = LHS, typename T = void>
struct HasEqualityOperator {
    static constexpr const bool value = false;
};

template <typename LHS, typename RHS>
struct HasEqualityOperator<
    LHS,
    RHS,
    std::enable_if_t<
        std::is_same<decltype(std::declval<LHS>() == std::declval<RHS>()), bool>::value>> {
    static constexpr const bool value = true;
};
template <typename T>
struct IsCString {
    static constexpr bool Eval() {
        using Tp = std::decay_t<T>;
        if (!std::is_pointer_v<Tp>) {
            return false;
        }
        return std::is_same_v<std::remove_cv_t<std::remove_pointer_t<Tp>>, char>;
    }

    static constexpr const bool value = Eval();
};

}  // namespace dawn

#endif  // SRC_DAWN_COMMON_TYPETRAITS_H_
